LIBREVILLE (Reuters) - If there is no recount of votes in Gabon's presidential election, the country will face "profound and sustained instability", the man who lost by less than 6,000 votes said on Friday.

Jean Ping has applied to the Constitutional Court to authorize a recount in a province where President Ali Bongo won 95 percent of the votes on a 99.9 percent turnout.

But he has already said he has no faith in the judicial body he thinks is too close to the government, and suggested on Friday that people would take to the streets if it does not order a recount.

"I strongly fear that a new false step by the Constitutional Court would be the cause of profound and sustained instability in Gabon," Ping told a news conference where he also called for an international inquiry into the killing of several of his supporters during post-election riots.

"If ... the Gabonese people don't accept the constitutional court's decision (if it rules against a recount), the people will assume their responsibility, and I will stand by their side," Ping said, hinting at a return to street protests.

Ping says between 50 and 100 people were killed in the riots after the election results were announced, much more than the government's death toll of six.

Ali Bongo, first elected in 2009 after the death of his father Omar who ruled the former French colony for 42 years, has accused Ping - a close ally of then-president Omar Bongo - of cheating in the August election.

EU observers said they found anomalies in the vote in Haut-Ogooue province where Ping is demanding a recount. France has called for a recount and the United States and European Union have urged the government to release polling station results.

France said on Friday it was closely following the case in the oil-rich Central African country which is home to 14,000 of its citizens and a permanent military base.

"(The court) must examine (the results) with transparency and impartiality and all means must be put in place to ensure the respect of its principles and establishment of the integrity of the vote," Jean-Marc Ayrault said in a statement.

Gabon recalled its ambassador to Paris in January after France's Prime Minister Manuel Valls appeared to question the legitimacy of Bongo's 2009 election, marking a new low in relations with the former colonial power with whom Omar Bongo enjoyed close ties.